The referenced copending application, assigned to the assignee of this application, U.S. Ser. No. 301,319, filed Sept. 11, 1981, BURGER, discloses a printing machine in which a support carrier for an operator is arranged to carry a guide roller, so that the path of a paper web can be changed, selectively, to permit ready access to the printing system, in dependence upon whether the operator stands on the support or not. The textbook "Techniken, Systeme, Maschinen" ("Technology, Systems, Machinery"), page 9, FIG. 17b, 2nd Fig. from left, Oscar FREI, published by Polygraph-Verlag, discloses a printing system in which a paper web is guided vertically, and the path is determined by guide rollers. The path is fixed. Application of a paper web to a printing machine from below permits relatively good accessibility to the lower printing cylinders; particularly when applied to newspaper printing machinery, however, such a paper path results in difficulties regarding accessibility with respect to the upper printing cylinders. It is difficult to reach the upper printing cylinders, for example to change their plates, since access to the cylinders is impaired by the paper web itself. Of course, it would be possible to place the path of the paper web which extends upwardly closer to the printing machine cylinders, so that the path of the web, entering the cylinders laterally, permit better access to the upper printing cylinders. If this solution is adopted, however, the paper web then will cover the lower printing cylinders, so that the access to the lower ones is impaired.